ARS | Publication request: MEASUREMENT OF DIETARY FIBER IN READY-TO-EAT MEALS USING NIR SPECTROSCOPY

Submitted to: Annual Meeting of the Institute of Food Technologists
Publication Type: Abstract Only
Publication Acceptance Date: March 10, 2005
Publication Date: July 17, 2005
Citation: Kim, Y., Singh, M., Kays, S.E. 2005. Measurement of dietary fiber in ready-to-eat meals using NIR spectroscopy [abstract]. Annual Meeting of the Institute of Food Technologists. Paper No. 54H-17.

Technical Abstract: Current methods of analysis of dietary fiber in ready-to eat (RTE) meals are very time consuming, labor intensive, expensive, generate chemical waste and require extensive sample preparation. A rapid method of analysis of total dietary fiber (TDF) that can be applied directly to RTE meals would be very advantageous. Rapid and environmentally benign methods of dietary fiber analysis have been developed for cereal foods using near infrared (NIR) reflectance spectroscopy. The objective of this study was to develop a rapid method of evaluating the total dietary fiber content of a wide variety of RTE meals using NIR spectroscopy. Samples were selected from retailers covering a wide range of TDF. Frozen, packaged, or canned meals were homogenized and NIR spectra obtained with a dispersive NIR spectrometer. TDF was measured by AOAC method 991.43 in defatted/dried samples. Based on fat and moisture loss, reference values were calculated for homogenized meals. Using NIR reflectance spectra (860 to 2496 nm) of homogenized samples and reference values for TDF, modified partial least squares (PLS) regression models were developed for the prediction of TDF in RTE meals. The modified PLS models were evaluated by cross validation and by prediction of an independent validation set. The SECV, range, and R2 of the five factor modified PLS model developed (n=114) were 0.99 % TDF, 0.6-9.2 % TDF, and 0.76, respectively. The model predicted TDF in independent validation samples (n=36) with SEP, range, and r2 of 0.97 % TDF, 0.32-8.53 % TDF, and 0.76, respectively. NIRS can provide a rapid method for screening TDF in RTE meals within minutes with very little sample preparation required, in contrast to the AOAC method, which takes 4-5 days to complete.